Method of manufacturing semiconductor device

Abstract

A semiconductor device manufacturing method which sequentially forms a gate oxide film and gate electrode material over a semiconductor layer of an SOI substrate and patterns the material into gate electrodes. The method further comprises the steps of forming sidewalls made of an insulator to cover side surfaces of the gate electrode; ion-implanting into the semiconductor layer on both sides of the gate electrode to form drain/source regions; partially etching the sidewalls to expose upper parts of the side surfaces of the gate electrode; depositing a metal film to cover the tops of the drain/source regions and of the gate electrode and the exposed upper parts of the side surfaces of the gate electrode; and performing heat treatment on the SOI substrate to form silicide layers respectively in the surfaces of the gate electrode and of the drain/source regions.

1. A semiconductor device manufacturing method which forms a MOSFET in an SOI substrate having an insulating layer between a semiconductor substrate layer and a semiconductor layer, said method comprising the steps of:
 forming a gate oxide film over said semiconductor layer; 
 forming a gate electrode on said gate oxide film; 
 forming sidewalls made of an insulator to cover side surfaces of said gate electrode; 
 ion-implanting into said semiconductor layer on both sides of said gate electrode to form drain/source regions in said semiconductor layer; 
 partially etching said sidewalls to expose upper parts of the side surfaces of said gate electrode; 
 depositing a metal film to cover top surfaces of said drain/source regions, a top surface of said gate electrode and the exposed upper parts of the side surfaces of said gate electrode; 
 performing heat treatment on said SOI substrate to form silicide layers respectively in the surfaces of said gate electrode and said drain/source regions; and 
 before said depositing a metal film, forming a plurality of grooves in the top surface of said gate electrode by etching said gate electrode, 
 wherein in said depositing a metal film, each of said plurality of grooves is filled with said metal film by sputtering. 
 
     
     
       2. A semiconductor device manufacturing method according to  claim 1 , wherein said metal film is deposited to have isotropic step coverage. 
     
     
       3. A semiconductor device manufacturing method according to  claim 1 , wherein said metal film is a cobalt film.